They LOVE spinach leaves!! I freeze them so they will soften upon thawing. I place a veggie clip on the stem & sink the spinach leaf. In a day my 4 otos have completely devoured it!! (Then back to algae & wafers until the next spinach treat!) They also like cucumbers, but I don't really so I never have them!

The biggest thing about keeping otos is to keep the water clean, ammonia at 0, nitrites 0 and nitrates 0 (I have live plants, so I have a small amount of nitrates). Give them a place to hide during the day, and enough to eat (but don't overfeed or they may not do as well with eating the algae!). They are my favorite fish, enjoy your little ones!!
Sharon